Embodiments of the inventive concept relate to semiconductor devices and, more particularly, to memory modules and memory systems including the memory modules.
A semiconductor memory is used to store data using semiconductor elements. The semiconductor memory can include a volatile memory such as a dynamic random access memory or a static random access memory, and/or a nonvolatile memory such as a flash memory, a phase-change memory, a ferroelectric memory, a magnetic memory, a resistive memory, or the like.
In general, volatile memory typically supports high-speed random access and is used as a main memory of a computing system such as a personal computer, a server, or a workstation. The nonvolatile memory typically supports a large storage capacity and is used as auxiliary storage of the computing system.
Nowadays, a storage class memory (SCM) is being researched and developed. The storage class memory that is being developed is targeted for supporting both a large nonvolatile storage capacity and a high-speed random access. The storage class memory may be implemented with a nonvolatile memory.
For compatibility with an existing main memory, the storage class memory is being researched and developed on the basis of a memory module of a main memory. However, a difference between an operating characteristic of the dynamic random access memory (DRAM) being a main memory and an operating characteristic of a nonvolatile memory may make it difficult to implement the storage class memory.